Vacuum packaging of various products between bottom and top sheets of plastic film is well known in the art. One of the latest systems is disclosed in U.S. Pat. No. 3,828,520 issued to Merritt. This patent itself includes an excellent discussion of prior art developments in this particular field.
The Merritt patent constitutes an improvement over the discussed prior art therein in the provision of protuberances on a platen which will serve to provide for airway passages in the withdrawal of air between bottom and top plastic sheets utilized to sandwich a product therebetween and effect a desired sealing.